K E Y W O R D S : baboon syndrome, clozapine, drug patch testing, drug reaction, SDRIFE, systematized contact dermatitis, vasculitis Symmetrical drug-related intertriginous and flexural exanthema (SDRIFE)is a benign drug reaction that is diagnosed clinically. We report a unique case of SDRIFE secondary to clozapine, confirmed by patch testing.
CASE REPORTAn 18-year-old man presented with high fever and pruritic red eruptions and pustules for 3 days. The rash appeared progressively on the axillae, legs, groin, and back over 2 days. About 2 weeks before, he had been started on lithium and clozapine due to mania. On examination, confluent erythematous papules, coalescing to form larger plaques, studded with pinhead-sized pustules, were present in the aforementioned sites. In addition, discrete purpuric papules over the dorsum of the feet and shins were noted (Figure 1). Mucosae were not involved. An infectious exanthematous rash or lithium-induced acute generalized exanthematous pustulosis (AGEP)/SDRIFE was considered as differential diagnosis.Workup for acute febrile illness was unyielding. Gram stain from the pustules showed scant neutrophils with no evidence of bacteria.Biopsy for histopathology from the pustular lesion showed spongiotic epidermis, and occasional necrotic keratinocytes overlying a dermis showing perivascular lymphohistiocytic infiltrates with extravasated red blood cells, which is consistent with SDRIFE ( Figure S1A,B); and 318 SUVARNA ET AL.